Evolutionary Theory Pre-Darwin
What did people think about life before Darwin?
They thought living things never changed.
What is evidence for evolution?
It is proof that living things change over time.
What are evolutionary agents?
They are things that cause change in living things.
What is natural selection?
It is when the best traits help animals survive.
What are modes of natural selection?
They are ways traits change in a group.
Example: What did Jean-Baptiste Lamarck think?
He thought animals could change during their life, like giraffes stretching their necks.
Example: What do fossils show?
Fossils show animals and plants that lived long ago.
Example: What is mutation?
A mutation is a small change in DNA.
Example: What is an adaptation?
A polar bear’s thick fur helps it stay warm.
Example: What is stabilizing selection?
Average traits are best, like medium-sized babies.
Example: What did Georges Cuvier study?
He studied fossils and showed that some animals went extinct.
How are bones evidence?
Animals like humans and whales have similar bones.
What is gene flow?
It happens when animals move and bring new traits.
Example: What is overproduction?
A frog lays many eggs, but only a few live.
Example: What is directional selection?
One side is best, like darker moths surviving.
What did James usher believe?
He believed in creationism which is in the bible.
How are embryos evidence?
Baby animals look similar early in life.
What is genetic drift?
It is when chance changes a group, like a storm.
Example: What is survival of the fittest?
Best adapted animals can escape danger and live.
Example: What is disruptive selection?
Both extremes are best, like big and small beaks.
Why were these ideas important?
They helped people start thinking about how life can change.
Why is evidence important?
It helps scientists understand how life changes.
Why do isolations matter?
They help populations change over time.
Why is variation important?
It helps create unique organisms.
Why are these important?
They show how traits change over time.